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1.
ACS Omega ; 8(5): 4727-4735, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36777608

RESUMO

Heterogeneous catalytic hydrogenation is an interesting alternative to conventional methods that use inorganic hydrides. The hydrogenation of acetophenone under heterogeneous conditions with the supported catalysts based on Ni is the most useful due to its redox properties and lower cost. As is well-known, catalyst support can significantly affect catalyst performance. We have investigated the influence of various physical-chemical parameters on the selective reaction of the hydrogenation of acetophenone by using different nickel catalysts on clinoptilolite supports, in four different forms: natural, previously modified with NH3 (Ni/Z+NH4 +), with HNO3 (Ni/Z+H+), and thermally treated (Ni/Z 500 °C). In particular, our work focuses on determining the influence of the mentioned physical-chemical parameters on the percentages of conversion and the selectivity of the catalysis. This study aims to identify the combination of parameters that allows for obtaining the best catalytic results. The identification of the physical-chemical parameters that determine the percentages of conversion and selectivity allows us to design optimal catalysts.

2.
Langmuir ; 38(39): 11972-11982, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36125418

RESUMO

Samples with micropores can not be adequately described by using the Langmuir isotherm. The Langmuir expression is obtained by using the monolayer assumption, which is not valid in samples with micropores. Then, we propose to include in the isotherm a corrective parameter related to the sample porosity. We show that the modified isotherm enables us to describe the experimental values for different samples (aluminas, clays, silicas, zeolites, and zirconias) in low and full relative pressure ranges. Indeed, a new thickness function for the adsorbate layer in terms of the relative pressure is proposed. Then, a better description of the external surface areas, mesopores, and micropores of the samples can be obtained with the new thickness function. The VBS model with this new thickness shows a better pore distribution description.

3.
Nutrition ; 85: 111139, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33549947

RESUMO

OBJECTIVES: The aim of this study was to evaluate the effect of the dietary supplementation of an alpha- and gamma-tocopherol mixture (1:5 ratio) in the adipose tissue expansion, hepatic steatosis, and expression of inflammatory markers induced by consumption of a high-fat diet (HFD) in mice. METHODS: Male C57BL/6 J mice were fed for 12 wk and divided into the following: 1) control diet (CD; 10% fat, 20% protein, 70% carbohydrates); 2) CD + TF (CD plus alpha-tocopherol: 0.7 mg/kg/d, gamma-tocopherol: 3.5 mg/kg/d); 3) HFD (60% fat, 20% protein, 20% carbohydrates); and 4) HFD + TF (HFD plus alpha-tocopherol: 0.7 mg/kg/d, gamma-tocopherol: 3.5 mg/kg/d). General parameters, adipocyte size, liver steatosis, adipose and hepatic tumor necrosis factor-α (TNF-α) and interleukin-1 ß (IL-1ß) expression, hepatic nuclear factor kappa B (NF-κB), and peroxisome proliferator-activated receptor α (PPAR-α) levels were evaluated. RESULTS: Tocopherol supplementation in HFD-fed mice showed a significant decrease in the body weight (19%) and adipose tissue weight (52%), adipose tissue/body weight ratio (36%), and serum triacylglycerols (56%); a 42% decrease (P < 0.05) of adipocyte size compared to HFD; attenuation of liver steatosis by decreasing (P < 0.05) lipid vesicles presence (90%) and total lipid content (75%); and downregulation of inflammatory markers (TNF-α and IL-1ß), along with an upregulation of hepatic PPAR-α expression and its downstream-regulated genes (ACOX and CAT-1), and an inhibition of hepatic NF-κB activation. CONCLUSION: The present study suggests that alpha- and gamma-tocopherol (1:5 ratio) supplementation attenuates the adipocyte enlargement, hepatic steatosis, and metabolic inflammation induced by HFD in association with PPAR-α/NF-κB modulation.


Assuntos
Dieta Hiperlipídica , Fígado Gorduroso , Tecido Adiposo , Animais , Dieta Hiperlipídica/efeitos adversos , Suplementos Nutricionais , Modelos Animais de Doenças , Fígado Gorduroso/etiologia , Fígado Gorduroso/prevenção & controle , Fígado , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Expansão de Tecido , gama-Tocoferol/farmacologia
4.
Biometals ; 32(1): 21-32, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30334122

RESUMO

Ideal drugs to cure cancer leave normal cells unharmed while selectively turning tumor cells unviable. Several copper complexes have been able to selectively slow down tumor proliferation. We hypothesized that Cu(smz)2(bipy)·H2O (1)-a copper-complex that has two ligands capable of interacting with DNA-would outperform Cu(smz)2(OH2)·2H2O (2), and also that supporting 1 on mesoporous silica spheres would decrease even further tumor cell viability in vitro. After exposing osteosarcoma cells (MG-63) and normal phenotype cells of bone origin (MC3T3-E1) to either complex, we studied their toxic effect and mechanisms of action. We determined cell viability (MTT assay) and quantified formation of reactive oxygen species (oxidation of DHR-123 to rhodamine). Moreover, we assessed genotoxicity from (i) formation of micronucleus (MN assay) and (ii) damage of DNA (Comet assay). After the exposure of 1 supported on silica spheres, we tested cell viability. Our results confirm our hypotheses: inhibition of tumor cells follows: supported 1 > dissolved 1 > 2. Future work that enhances the load of the complex exclusively in mesopores may improve the ability of 1 to further inhibit tumor cell viability.


Assuntos
2,2'-Dipiridil/farmacologia , Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Cobre/farmacologia , Microesferas , Osteossarcoma/genética , Osteossarcoma/patologia , Sulfametazina/farmacologia , 2,2'-Dipiridil/química , Células 3T3 , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Cobre/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos , Estrutura Molecular , Osteossarcoma/tratamento farmacológico , Osteossarcoma/metabolismo , Tamanho da Partícula , Porosidade , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Dióxido de Silício/química , Relação Estrutura-Atividade , Sulfametazina/química , Propriedades de Superfície
5.
Univ. odontol ; 20(42): 80-83, oct. 2000.
Artigo em Espanhol | LILACS | ID: lil-395278

RESUMO

El propósito de esta investigación fue observar si la presencia de OP-1 sobre las superficies radiculares dependía del tratamiento que ésta recibiera. Se obtuvo una muestra de dientes de pacientes con exodoncia indicada por periodontitis del adulto avanzada localizada, los dientes de la muestra fueron distribuidos en 3 grupos de diez muestras cada uno.


Assuntos
Periodontia , Periodontite , Histologia , Colômbia
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